SEAL-O-RING 7Y4277 - Caterpillar

The engines may be equipped with various optional engine features and controls. This section discusses the general information about these devices and the operation of these devices.
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C-10 and C-12 Truck Engine (1) Coolant temperature sensor (4) Inlet manifold air temperature sensor (5) Engine oil pressure sensor
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3406E Truck Engine (1) Coolant temperature sensor (2) Fuel temperature sensor (3) Atmospheric pressure sensor (4) Inlet manifold air temperature sensor (5) Engine oil pressure sensor
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C-15 and C-16 Truck Engine (1) Coolant temperature sensor (2) Fuel temperature sensor (3) Atmospheric pressure sensor (4) Inlet manifold air temperature sensor (5) Engine oil pressure sensorCoolant Temperature Sensor
The engine coolant temperature is measured by an electronic sensor that is mounted on the water outlet housing. The signal for the engine coolant temperature sensor is used to modify the engine fueling and the signal is used to modify the engine timing. By modifying the engine fueling and the engine timing, the engine will improve the following conditions: cold start capability and white smoke cleanup. The ECM supplies the coolant temperature sensor with 5.0 .5 VDC. The sensor output voltage is 0.5 to 4.5 VDC. The sensor output voltage depends on the engine coolant temperature. Coolant temperature is used in order to indicate the Cold Mode Operation. Coolant temperature is also used for Engine Monitoring.Fuel Temperature Sensor
The fuel temperature is monitored in order to adjust the calculations for the fuel rate. The fuel temperature is monitored for the power correction when the fuel temperatures exceed 30 °C (86 °F) in order to provide constant power. The value for the power correction for the maximum power is 70 °C (158 °F). Fuel temperature that exceeds 90 °C (194 °F) for ten minutes causes a diagnostic code to be logged.Atmospheric Pressure Sensor
The atmospheric pressure sensor is an absolute pressure sensor that measures crankcase pressure. The atmospheric pressure sensor is used to calibrate the other pressure sensors on the engine. The values for these sensors that are communicated over the data link are calculated by subtracting the atmospheric pressure sensor reading. The atmospheric pressure sensor measures pressure from 0 kPa (0 psi) to 116 kPa (17 psi). The atmospheric pressure sensor is supplied with 5 VDC by the ECM.Inlet Manifold Air Temperature Sensor
The sensor for the inlet manifold air temperature measures the temperature of the air in the inlet manifold. The Electronic Control Module (ECM) monitors the sensor signal for the inlet manifold air temperature. The output of the ECM can indicate high inlet manifold air temperature through a relay or a lamp. The sensor for the inlet manifold air temperature will not cause a shutdown of the engine or any horsepower change.Note: The sensor will be affected by the heat that is conducted from the air in the inlet manifold when the engine is idling, and after the engine is shut off. This warm-up is due to the lack of coolant circulation through the engine. The reading from the sensor for the inlet manifold air temperature